Coreference resolution system contains two main tasks: one task is to detect the valid mentions appearing in a given context, and the other is to group mentions into different clusters such that mentions in each cluster point to the same target entity. The coreference systems can be either heuristic rule-based models [1]}, [2]} or feature-based machine learning structures [3]}, [4]}, [5]}, [6]}, [7]}. One of the main challenges of these systems is that they requires hand-crafted heuristic rules and features, which can be difficult to scale and hardly cover all coreference relations.
